The usually buttoned-up Mitt Romney repeatedly gave a thumbs-up. He passed around dozens of high fives. And at every stop, he clapped the back of his new sidekick, Paul Ryan.

HIGH POINT, N.C. — The usually buttoned-up Mitt Romney repeatedly gave a thumbs-up. He passed around dozens of high fives. And at every stop, he clapped the back of his new sidekick, Paul Ryan.

This was Romney unplugged, clearly energized by his youthful running mate and thrilled with the enthusiasm it's created among Republicans in the opening act of the new team.

"I am so happy! I am so happy to have my teammate now," Romney told cheering supporters in Mooresville, N.C., on Sunday at the first of two North Carolina rallies where thousands spilled into the streets outside, eager to see the GOP ticket.

He was so happy, in fact, that when the crowd inside the venue broke into Romney's speech to chant, "USA, USA," Romney joined in — and pumped his fist in the air. He was right in step with Ryan, who was standing on stage with him doing the same thing.

The presidential candidate voters here saw was far different than the restrained and ever-cautious White House hopeful of the muted days of the early primary campaign. Back then, Romney drew smaller crowds and his interactions with voters were rote. If crowds chanted, he would wave and smile. Sunday was also a marked shift from last month, when Romney embarked on a weeklong foreign trip marred with mistakes that, by the end, had him appearing strained and distant.

The change happened Saturday when he announced Ryan as his No. 2 in Norfolk, Va., the USS Wisconsin as a backdrop before a jubilant crowd. The party's conservative base, long suspicious of Romney, reacted as if it finally had a reason to believe.

Thousands came to see the GOP ticket at a furniture company in High Point, N.C., on Sunday near Greensboro. About 1,500 waited — some more than five hours — in a cavernous warehouse with struggling air conditioning, while 2,000 packed into a cleared-out furniture showroom where the air was sticky and heavy. Thousands more stood behind barriers erected on the street outside — Romney and Ryan stopped on their way in to give high fives to a few in the cheering crowd.

"We love you!" Romney cried. He grinned, sweat beading on his brow, and clapped Ryan on the shoulder. Aides have dubbed Ryan "the partner."

As Romney's campaign plane prepared to take off for Ryan's home state of Wisconsin for an evening rally, Romney sat on the arm rest of his aisle seat and chatted with Ryan, both men talking with animation. One of Ryan's sons tried to interrupt, but Ryan waved him gently away.

The Romney-Ryan chemistry has been clear since well before Ryan joined the ticket.

They campaigned together in Wisconsin before the primary there, joking and laughing in sandwich shops and at rallies. They appeared as much like father and son as two politicians. Ryan, 42, even played into Romney's own offbeat sense of humor, participating in an April Fool's joke at the presidential candidate's expense. Romney showed up at a supposed campaign event where he heard Ryan calling him "the next president of the United States" — only to find the room nearly empty.

Their families clearly get along. Ryan's daughter Liza and Romney's granddaughter Chloe hugged each other on stage in Manassas, Va., at one point standing with arms around each other holding matching "Romney-Ryan" placards. Romney's personal aide, Garrett Jackson, posted pictures on Twitter of all the Ryan kids — Paul and Janna have two sons, Sam and Charlie — and two Romney granddaughters, Chloe and Mia, playing together.

Romney, it seems, couldn't be happier.

"It's now two on two instead of two on one," he said late Saturday as his campaign plane carried the newly minted ticket from Virginia to North Carolina. "This is good. They've got someone else to pick on, too!"